Tens-control device for sprocket wheel calculating machines



United States Patent [72] inventor Gottfried Burkhardt Winkelhaid,Germany [21'] Appl. No. 804,759 [22] Filed Mar. 6,1969 [45] PatentedDec. 29, 1970 [73] Assignee DIEHL Nurnberg, Germany [32] Priority Mar.6, 1968 [33] Germany [31] No. 1,574,990

[54] TENS-CONTROL DEVICE FOR SPROCKET WHEEL CALCULATING MACHINES 5Claims, 5 Drawing Figs.

[52] US. Cl 235/137, 235/142 [51] Int. Cl G06c 15/26 [50] Field ofSearch235/137, 142, 133, 139

[56] References Cited UNITED STATES PATENTS 2,588,835 3/1952 Herzstark235/137 2,667,307 1/1954 Westinger et a]... 235/137 3,102,688 9/1963Gang 235/137 3.456.877 7/1969 Juhas ABSTRACT: A tens-control apparatusfor sprocket-wheel calculating machines having sprocket-wheel bodies andvalue sprockets additionally provided with a tens-control sprocketradially shiftable and engageable with a driven wheel of acountermechanism. Sprocket-wheel amount-control deviceforming meansinclude countermechanism carriage means shiftable and operative relativeto ten-toothed counterwheel means in each position having two sprocketswith teeth evenly extending into rotation range of sprocket-wheel bodiesshiftable with respect to valveand tens-control sprockets of theamount-control device respectively at a time for additive andsubtractive calculating. Control shift means formed particularly withguide members of a tens-control lever extend over an angular range ofthe sprocket-wheel bodies engageable with respect to two counterwheelmeans. The control-shift means is adapted to maintain deflection of thetens-control sprocket of the next higher located amount-control deviceduring resultant tens preparation. A tens-control lever alternately isformed as a ring body provided with a groove extending in circulararc-forming manner within range of the counterwheels ot'the carriagemeans.

PATENTED naczs mm SHEET 1 OF 2 INVENTOR Gottfried BURKHARDTPATENTEDnaczsBm 3,550,846 31am 2 BF 2 IN VEN TOR. Gottfried BURKHARDTTENS-CONTROL DEVICE FOR SPROCKET WHEEL CALCULATING MACHINES Thisinvention relates to a tens-control device for sprocketwheel calculatingmachines of which the sprocket wheel body .in an addition to the valuesprockets still has for each a loose radially shiftable tens-controlor-shift sprocket provided therewith, to be shiftable as provided to bedisplaced in helical formed or screw spiral manner place-for-place. Thetens-control sprocket becomes coupled through guide members of atens-control lever radially with the driven or secondary drive wheel ofthe counter in the respective position during the running-throughoperation. The coupling occurs so far as the tens-control cam or cog ofthe next lower position passes through null or zero and the tens leveris deflected into the tens-control position.

It is known to provide with sprocket-wheel-value-or amount-controlmechanisms in which the sprocket-wheel bodies in addition to the ninevalue sprockets still each have a tens-control sprocket displaceablefrom place-to-place in a screw-spiral-forming manner. While the valuesprockets are releasable or disengageable radially by means of apresetcam disc, the tens-control sprockets are releasable or disengageableonly from event to event at a time, when a tens overlay follows in thenext lower place or position. The control of tens sprockets of thistype, for example described in the German Pat. 569,599, occurs foramount control mechanism in a known manner, described in German Pat.574,487, through a tens-control or shift lever provided with two clawsor prongs. The tens-control lever commands or dominates a tens-controltooth shiftable loosely on a sprocket wheel. The tens-shift lever on itsside is so set for tens control through the control or shift cam or cogof the counterwheel that the tens-control tooth is brought intoengagement with the tooth wheel of the next higher place or positionthrough the tens-control lever and the counterwheel is shifted ahead byone step.

For selective additive and subtractive calculating with a value oramount control mechanism of the type named, it is necessary to use avalue or amount control mechanism having two sets of tens sprocketsrotatable in one of two-directional movement; due to forced or positivemanner of drive there is unusable angular range; also due to the size ofthe moving masses, the turning count at a time and thereby thecalculating speed is limited; or selectively it is possible to provideengageable intermediate wheels. This means, however, that there is needfor multiplicity of parts as well as space and requires a higherfabricating accuracy. A high calculating speed is attainable with suchmachines, especially when a high place or position capacity is required,preferably through separation of the calculating and tens-controloperation.

The purpose of the present invention is to provide a straightforwardcalculating mechanism involving use of a value or amount controlmechanism and a tens-control device of the previously identified typeand having a minimum complexity of countermechanism wheels. A furtherobject of this invention is to provide a calculating machine whichoperates also at high calculating speed satisfactorily forcountermechanism carriage shifting from place-to-place at a minimum ofoperating steps and therewith requiring a minimum of time. The goal ofthe present invention is also to provide a calculating machine thatoperatesquietly as well as I mechanism with a tens-control deviceaccording to the present invention; and

FIG. 2 is a sectional side view of one location or place of thecalculating mechanism with a tens-control lever of a further embodimentin accordance with the present invention;

FIGS. 20, 2b and 2c illustrate further detail of mechanism in accordancewith the present invention. I

For the solution of this problem there are provided tentoothcounterwheels with respect to the counterdevice carriage shiftable alongthe fixed or stationary sprocketwheelamount control mechanism in eachposition having two teeth mating with each other extending into therotating range of the sprockets displaceable with respect to each otheraxially by approximately sprocket width. The ten-tooth counterwheels areadapted to shift the counterwheels provided with the tens-control cam orcog during addition and otherwise to shift the same in the range of thevalueand tens-com trol sprockets of the amount control mechanism at atime during subtractive calculating. The guide members of the involvedcontrol shift formed as tens-control lever extend over an angular rangeof the sprocket-wheel body covering or corresponding to the engagementrange of both counterwheels. With resultant tens preparation, thetens-control sprocket is therefore held in mating form relationship withrespect to the next higher value control device position over thecollective previously noted angular range displaced into tens-controlposition.

According to a further characteristic of the present invention, thetens-control lever can be formulated as a ring body which is providedwith a closed loop radially extending groove with respect to the tenssprocket of the nextlhigher amountcontrol-device position. The groove isformulated approximately in an 0-form and runs at least in a circulararc-forming manner in the range of the counterwheels of the carriage.The tens-control-ring body is pivotable or swingable thereby, analogouswith respect to the initially described tens-control lever, against theforce of a spring through a tens-lever controlled or regulated from atens-control or shift cam or cog into the tens-shift position. Thetens-control-ring body there latches itself by means of a stop nose orprojection at a corresponding part releasable toward the end of eachcalculating shaft rotation. The tens-control-ring body is preferablymade of an easily workable material, especially molded out of a toughelastic thermoplastic synthetic material (Delrin or acetal resin orpolyamide materials).

The inventive tens-control apparatus makes it possible to operate withtwo toothed wheels at a time per location and thereby the carriage canbe shifted without raising and lowering from one location to another.The small or minimum number of movable parts as well as the reductionofinertia mass permits attainment of a high-speed calculating operation.Due to the direct engagement of the value-and tens-control sprocketsinto the counterwheel to be turned at a particular time, there isavoidance of tolerance difficulties. The short drive train permitsbacklash-free operation without special safetymeans. Furthermore, themachine operates for calculation in a quiet and smooth or jerk-freemanner in comparison with previously known machines.

Referring more particularly to FIG. 1, on an amount-control shaft 1there are sprocket-wheel bodies 2,3 secured thereon and which provideother than nine value sprockets 4,5, additionally tens-control sprockets6,7 as installed from the bottom toward the top staggered for eachposition at a time for position spiral-forming relationship. The valuesprockets 4,5 are caused to move or travel radially in a known manner bymeans of value setting cams. The tens-control sprockets 6,7 are guidedto be loosely radially shiftable in the sprocketwheel bodies 2,3. Thetens control sprockets 6,7, however, also can be biased or held inwardlyor outwardly by means of springs. As can be seen on the tens-controlsprocket or spoke 7, there are sprocket teeth 6,7 carried on an arm,spar or overhanging beam 8 which extends into the range of the nextlower position at that time.

Along the amount control mechanism provided stationarily in the machinethere is a shaft or an axis-forming means extending transversely throughthe machine upon which the countermechanism carriage 10 is shiftable andis journaled or supported in a limited swingable or pivotable manner. Ineach operating position this countermechanism carriage 10 hascounterwheels 13,1 4, particularly 15,16 'rotatably journaled i on twoaxes or shafts 11,12, extending with their teeth into the rotating rangeof the value-and tens-control sprockets 4,6, particularly 5,7 matingwith each other and axially displaced with respect to each other byapproximately a sprocket width. In the positive (additive) carriageposition, the sprockets 4,6,

, particularly 5,7 drive the counterwheels 13, particularly 15, and inthe negative (subtractive) carriage position in contrast thereto, thesprockets 4,6, particularly 5,7 engage with coun- 'terwheels 14,particularly. during rotation of the amount-cona circular formed discmeans 22,23 of the sprocket-wheel bodies 2,3 respectively, in theinoperative stop or rest position The tens-control levers 18,19 providea U-formed slide guide means 24,25 in a coulisse or rocker arm manner tothe next higher amount-control-device position. During each'amount-control-shaft rotation, the tens-sprocket or spoke 7 of the armor overhang beam 8 runs into'the slide guide means 24. if thetens-control lever 18 is in the illustrated stop or rest position,accordingly the tens-sprocket orspoke 7 is radially retracted andproceeds ineffectively or inoperatively over the counterwheel orcounterwheel 16 in operative alignment at the time.

Each of the counterwheels 13,15 has a tens-releasing cam or cog 26provided therewith. In the rotating range of this tens-releasing cam orcog 26 there extends an abutment or engageable tooth 27 of a tens-leverjournaled to be pivotable or swingable upon an axis or shaft 29 againstbiasing force of a spring means 28. The tens-lever 30 engages with anarm or overhanging beam 31 of a side or lateral flange, tang or lug 32ofthe tens-control lever18. As the cam or pawl 26 travels during passagethrough null" of the countermechanism against the striker or engagementtooth 27, either from the front or from behind, which means duringrotation of the counterwheel 13 counterclockwise or clockwise indirection, the tens-lever 30 in this way shifts or pushes thetens-control lever 18 with its slot 47 upon the axis or shaft 17,particularly the guide member or part 20 upon the disc 22. Thereby anose or projection 33 of the tens-control lever 18 snaps into a cutoutor recess 34 of a stop or rest spring tongue 35 of a spring comb ormating flange 36 and hooks itself into engagement therewith. lf now thetens-sprocket sprocket or spoke 7 of the arm or overhanging beam 8travels into the slide guide means 24, which furthermore forms acircular are having a predetermined angular range collectively withrespect to the coun- 1 terwheels 13,14, respectively, 15,16, then thetens-sprocket or spoke 7 is radially outwardly displaced, engages thecounterwheel 15 or 16 corresponding thereto at the particular time, andshifts the same one-step further by one unit.

Upon the amount-control shaft 1 there is also a disc 37 with aneccentrically installed side or lateral stud or pin 38 secured thereto.in the turning range of the pin or stud 38 there ex- 1 tends a slopedportion or an inclined piece 43 of a swingable trol lever 18. Finally,by means of a leaf spring 44 of a spring comb 45 lying upon an extension46 of the tens-control lever 18 the parts are shifted back into thestarting position and engaged with a guide piece 20 on the circular disc22. The spring 28 serves for resetting the tens-lever 30.

The lowering or dropping and raising of the countermechanism carriage 10results with respect to a shaft 49 rotatably journaled in a sidewall 48.The shaft 49 at an end thereof carries a partially toothed or segmentedgear wheel 50 which engages with a track 51 supported by the shaft 49relative to a cutout or recess ofthe carriage wall 10. This cutout islimited from below by means of a flange or flap 52 which engages againstor lies against the shaft 49 when, in the illustrated control position,the carriage 10 is coupled or engaged with the amount-control mechanism2,3, whereby the track or rail 51 supports the carriage 10-along anincline 53. [f the shaft is rotated or pivotally swung in the directionof an arrow .b, then the track or rail 51 next engages a slit 54 of thecarriage 10, pivots or swings the same downwardly .until an upperprojection or overhanging beam 55 of ;the carriage' l0 liesor engagesupon the shaft 49 and then supports the carriage 10 upon a lower incline56. In the downwardly pivotally swung position the counterwheels 14, 16mate in every position with respect to the corresponding toothed rod ofthe amount-control mechanism. Of the toothed rod there is only onetoothed rod 57 illustrated in the drawing, namely,'the lowermostillustrated or represented amount-control mechanismlocation 2.

In comparison with calculating mechanisms with which thecounting-mechanism carriage is lowered into a neutral inter- I mediateposition at a time for transporting thereof, which means for each stepfrom position to position, it is possible to control or further shiftthe carriage 10 of the present machine in the coupled carriage positionillustrated without energization or actuation of the previouslydescribed arrangement 48 through 56. This is possible because as aresult of cost reduction and savings of intermediate wheels while thecounterwheels 13,14, respectively, 15,16 16 provide carriage transportupon a circular arc around the amount-control shaft 1, which means thatboth are equally far away from the sprocketwheel bodies 2,3 at the time,and stand or are located across from the starting angular position ofthe amount-control mechanism having a toothless part of-the previouslynoted sprocket-wheel bodies 2,3. The carriage 10 is lowered only forassuming or taking over values and for summationstroke or movement andthereby is coupled into the setting tooth rods 57. Stop or rest pawls ordetents 61 provided with the counterwheels 13,15 for each positionthereby are pivotally moved or swung into an ineffective or inoperativeposition.

During summation the abutments or nose projections 27 of the tens-lever30 serve to limit the tens-releasing cams or cogs 26 while thetens-lever 30 is supported by an arm 58 upon the shaft 49 duringdropping or lowering of the carriage 10.

Concerning the tens-control levers 18 and 19, respectively, it is alsoto be noted that the guide members 24,25 thereof are formed in aU-shaped profile and form a funnel-shaped widened inlet or'entrancewhereby an outer wall 59 is pulled rearwardly so far that the arm oroverhanging beam 8 engages also within the tens-control sprocket orspoke 7 of the next higher amount-control mechanism position, when thesprocket or spoke 7 is displaced radially outwardly. Conve rsely, thereis an inner wall 60 extending inwardly so far to the amount-controlshaft 1 that the arm or overhanging beam 8 is picked up and guided intothe slide guide means 24,25. When the sprocket or spoke 7 has beenshifted into place, the tenscontrol lever means 18,19 are shifted,however, through an existing null passage into the next lower positionin the te nscontrol location or position and the guide members 24,25 arethereby caused to be radially further removed from the amount-controlshaft 1, more particularly the circular discs 22,23. 1

As already noted, the guide members 24,25 form an approximately circularare having a midpoint in the axis of the amount-control mechanism 2,3over an angular range in which toothed engagement of the tens-controlsprocket or spoke 7 is possible into the counterwheels'15,16,respectively. The slide guides, that is, the upwardly extending orpulled sidewalls thereof, are smoothened inwardly or to the inside andpreferably are entirely hardened. As a result of the shifting-swingingmovement during the deflecting of the tens-control levers 18,19 into thetens-control position, there results a click-free or thump-free movementof the tens-sprocket orspoke.

In the event the tens-control sprockets or spokes 6,7 are held retractedin a stopped or rest position by means of the springs in the sprocketwheel bodies 2,3, it is sufficient to provide the tens-control levers18,19 with only the inner wall 60. If the tens-control sprockets 6,7thereagainst stand in the starting position with all radially extendingforwardly, then the outer wall 59 extends sufficiently forineffectiveness or inoperativeness of the same at a particular timeduring the over running of the counterwheels 13,14, respectively, 15,16.

Instead of forming the tens-control lever as a control pusher orshifter, the same is formed as a ring body 62 in the illustratedembodiment of FIG. 2. The ring body 62 is pivotally movable or swingableabout an axis or shaft 17 rigid with respect to the frame. Thetens-control body or ring body 62 provides an approximately O-formedgroove 63 with respect to the next higher sprocket wheel body(corresponding, for example, to that identified by reference numeral 3,(in FIG. 1). The groove 63 radially leads or guides the side orlaterally located arm or overhanging beam (corresponding to thatidentified by reference numeral 8, in FIG. 1) of the tens-controlsprocket or spoke (corresponding to that identified by reference numeral7, in FIG. 1) over a full rotation or turn of the amount-controlshaft 1. Accordingly, the groove 63, as can be seen from FIG. 2, is onlysomewhat wider than the arm or overhanging beam 8 in the range of thecounterwheels 13,14 respectively, 15,16 in a circular arc-shaped andradial manner. Displaced by 180 with respect to the counterwheels 13,14,which means in the juxtaposed upper part lying across therefrom,however, the groove 63 is preferably so wide that here, also, thetens-control sprocket or spoke 7 is not radially displaced duringunattained tens release. Therefore, the tenssprocket or spoke 7 duringunreleased tens-control is engaged into the sprocket-wheel body 3 duringoperation through the range of the counterwheels 13,15 and 14,16 andduring previously released tens-control in contrast projecting radiallyfrom the sprocket-wheel body 3.

Also the tens-control-ring body 62 includes an abutmentor stop 64against which the arm or overhanging beam 31 of the tens-lever presseswhen the tens-release cam or cog 26 runs against the engagement orabutment tooth 27 of the tens-lever 30. Thereby the tens-control-ringbody 62 is swung or pivoted against the force of a leaf spring 44 aroundthe axis or shaft 17 in the direction of the arrows c and engages orlatches itself with respect to a stop nose or projection 65 in alatching counterpart 66. The latching counterpart 66 is pivotable orswingable against the force of a spring 67 about an axis or shaft 68 ina manner not illustrated in FIG. 2 but, similar to that of FIG. 1 islatchable or engageable at the end of the amount-controlshaft rotation,which means liftable away from the stop nose or projection 65.

The tens-control apparatus in accordance with the present inventionmakes it possible to operate with only two gears per place at a time andthereby the carriage can be shifted without lifting and lowering thereoffrom place to place. Previously known calculating machines of this typerequire up to four wheels or gears per place. The minimum or nominalnumber of movable parts as well as the reduction of mass moments orforces permits calculating speed now to be attainable which waspreviously not known. Due to the direct engagement of value andtens-control sprockets in the gear or counterwheel turned at aparticular time, it is possible to avoid tolerance difficulties. Theshort drive chain permits attainment of correct calculation withoutparticular safety means and by way of operation with a minimum of play.Additionally, the machine operates in a quiet and smooth manner.

The illustration of FIG. 1 described previously represents a perspectiveexploded representation of parts viewed with two adjoining places of amechanism for amount shifting with a tens-control apparatus.

FIG. 2a shows a variation of the arrangement of FIG. 1 as a sectionalside view with a sprocket-wheel body means of the three next-lower valueplaces, whereby the tens-control sprocket of the'represented sectionalparts is drawn without guide means (shifting-wheel bodies);

FIG. 2b is a sectional view taken along the line lIb-Ilb through thesprocket-wheel according to FIG. 2a; and

FIG. 20 shows the track of the value sprockets and the helically formeddisplaced tens-sprockets respectively the counter or numerical wheelsmeshing with the sprockets.

According to FIG. 1, there are provided sprocket-wheel bodies 2,3 uponan amount-control shaft 1. A sprocket disc 2' respectively 3' is securedin fixed relationship upon the shaft and a rotatable adjusting orsetting disc 2" respectively 3" is provided upon the front side or endsurface of the sprocket disc as viewed and these represent the essentialconstruction elements of a sprocket-wheel body. The sprocket disc orplate itself includes in addition to nine value sprockets 4,5additionally a tens-control sprocket 6,7. The tens-control sprockets ofthe individual sprocket-wheel bodies are staggered against the directionof rotation in helical or screwthread form. Certain sprockets are guidedin beam-forming extension of grooves 6' of the sprocket-wheel bodies.The value sprockets 4,5 each have a laterally projecting spur 4',respectively 5', which engages in one of the centerinterrupted channels4" of the setting discs or plates 2", 3"; the same are shifted in aknown manner by means of setting discs radially and form a toothedelement in shifted condition as can be seen from FIG. 2a. Thetens-control sprockets 6,7 laterally provide a bracket crossbar or spar8 which when viewed rearwardly in the drawing extends only through anindicated window 8 of the sprocket disc or plate and into the range ofthe next lower place at a particular time. By means of the window, thepath of the otherwise loose tens-control sprocket is limited in thecorresponding groove located with respect thereto. In another embodimentnot illustrated, the tens-control sprockets are held in their particularposition by way of spring means.

For fixation ofa set position of the setting discs or plates 2", 3",there is a stop or register sprocket 69, respectively 70 serving foreach thereof. This is likewise guided in a groove of the sprocket discor plate and the same is pressed outwardly in the stop or regulatingtooth means 71, respectively 72 in a manner not separately illustrated.Additionally, the previously freely movable stop or regulating sprocketis arrested after setting by way of lateral shifting of a wedge 73provided therewith.

Along the stationary provided amount-control mechanism in the machine,there is provided a shiftable countermechanism carriage 10 upon an axis9 extending transversely with regard to the machine and the same isjournaled in restricted or limited swinging range. In each value placethere is provided with this amount-mechanism carriage 10 means includingtwo tens-control sprockets 4,6 respectively 5,7 with projectingcounterwheels 13,14 respectively 15,16 upon axes 11,12 rotatablyjournaling the same adapted for meshing with each other and shiftablewith respect to each other approximately for a sprocket width in axialdirection (FIG. 20) with the teeth thereof having a rotating rangeaccordingly. In positive (additive) carriage positioning thenumber-wheels 13,15 and with negative (subtractive) carriage positioningthe number-wheels 14,16 are shifted axially into the rotating range ofthe valueand tens-control sprockets 4,6 respectively 5,7, so that thesame during rotation of the amount-control shaft 1 in the direction ofthe arrow a are found in the same engaging sense.

Upon a frame-fixed axis 17 there are tens-control levers 18,19 journaledby means of elongated slot means 47 and the same are formed as shiftersfrom each of which in the inoperative rest position there is asprocket-wheel body means 2, respectively 3 located thereon with a guideor slide member or piece 20,21 engaging upon an arcuately formed disc orplate 22,23 For the next higher amount-control mechanism place orposition, there are tens-control levers 18,19 in a guide-type orcoulisse-type U-formed slide guide 24,25. The spar or projection 8 ofthe tens-sprocket 7 runs into the slide guide means 24 during eachamount-control shaft rotation. If the tens-control lever 18 is locatedin the represented rest position, then the tens-sprocket 7 is retractedradially and runs ineffectively over the fleeing set counterwheel 15 or16.

Each of the number-wheels 13,15 is provided with a tensreleasing thumbor projection means 26. In the operating range of this tens-releasingthumb 26 there projects an abutment tooth 27 of a tens-lever 30journaled pivotally upon an axis 29 against the force of a spring 28.The tens-lever 30 engages with a spur 31 of a lateral flap 32 of thetens-control lever 18. The thumb 26 runs against the abutment tooth 27during zero passage of the countermechanism whether from the front orfrom the rear as previously noted.

With an embodiment illustrated in FIGS. 20, 2b and 20, there is a ringbody 62 discernible as on the inner radii relative to which pivotalmovement can occur upon a frame-fixed axis 17 for each of thesprocket-wheel bodies of which only the sprockets 4 and 6 are drawn inFIG 2a in value positioning or place two" and the channel 4", throughthe same is not shiftable in axial direction. The outermost dotted linedesignated radius hereby designates the effective and followingineffective sprocket path or track. Towards the next highersprocket-wheel body there is represented only the tenssprocket 7 and aring body is provided thereon with respect to the approximately -formedgroove 63 upon the side as seen in the illustration. The same guides thelateral spar or projection 8 of the tens-control sprocket radially overa complete rotation of the amount-control shaft 1. The groove 63 extendsin the range ofthe number-wheels 13,14 respectively 15,16 in an arcuateform and in this location the same is only slightly wider than the sparor projection 8. Displaced by 180 with respect to the number-wheels,which means in the oppositely located upper part, the groove 63 incontrast thereto is so wide that here the tens-control sprocket 7 is notradially shifted out in the basic position. As a result, thetens-sprocket 7 is found in the position illustrated during passage ofthe number-wheels 13,15 and 14,16 in a radially retracted position inthe sprocket-wheel body 3. With previously released tens-control incomparison, the tens-sprockets is found in a projecting positionextending radially from the sprocket-wheel body. The counter ornumber-wheels 13,15 each has provided therewith a tens-releasing thumbor projection 26. In the running or operating range of this thumb, thereextends, moreover, the abutment or stopping tooth 27 shown in FIG. 20which is journaled on the axis 29 and which is pivotable or swingableagainst the spring force with respect to the tens-lever 30 which presseswith the projection or spur 31 against the abutment 64 of the ring bodywhen the thumb or projection upon passing through a null positionoperates in a manner, in other words, such that during turning orrotation of the number mechanism against or in clockwise directionagainst the abutment tooth, thereby the ring body 63 is swung againstthe force of the leaf spring 44 around the axis 17 in the direction ofarrow 0 and the same stops or comes to a rest with a rest nose 65 in alatching mating piece 66 which is pivotable against the force of aspring 67 about an axis 68. In a manner not illustrated though similarto the illustration of FIG. I, at the end of the amount-control shaftrotation the same is unlatchable or in other words can be lifted out ofthe rest nose 65. The wedge 73 provides an arresting means describedwith a preceding embodiment.

It is, of course, to be understood, that the present invention is by nomeans limited to the particular construction shown in the drawings, butalso comprises any modifications within the scope of the appended claimsm I claim:

1. A tens-control apparatus for sprocket-wheel calculating machineshaving sprocket-wheel bodies each in addition to value sprockets alsobeing provided with a tens-control sprocket spirally displaced fromposition to position, loosely radially shiftable, and which can becoupled with a driven wheel of a countermechanism through guide membersof a tens-control lever in the pertaining position during runningprocedure, comprising: means forming a sprocket-wheelamount-controldevice structurally located in a stationary position and relative towhich countermechanism carriage means can be shifted, ten-toothedcounterwheel means provided operatively with said carria e means in eachposition having two sprockets displaced wit respect to each other byapproximately sprocket width and having teeth thereof evenly extendinginto rotation range of sprockets of the sprocketwheel bodies whenoutwardly shifted radially thereof into mating relationship relative toeach other, counterwheels provided with tens-release control cam meansand including at least a pair of wheels which are shifted axially intorange of valueand tens-control sprockets of the amount-control devicerespectively at a time for additive and subtractive calculating, andcontrol-shift means formed particularly with guide members of thetens-control lever and extending over an angular range of the sprocketwheel bodies in engagement range with respect to two of the counterwheelmeans, said control-shift means being adapted to maintain deflection ofthe tens-control sprocket of the next higher-located amountcontroldevice during resultant tens preparation in radially coupled formationover collective angular range.

2. A tens-control apparatus according to claim 1, in which saidsprocket-wheel bodies include a guide disc, a shaft defining astructurally fixed axis journaling each tens-control lever to beswingable and shiftable with respect to slot means thereofrelative tothe axis of said shaft, a nose projection and a slide portionrespectively also being provided with the tenscontrol lever, springmeans urging said slide portion against said guide disc, and a springtongue engageable by said nose projection upon release of tens-controloperation.

3. A tens-control apparatus according to claim 1, in which a ring bodyforms the tens-control lever and is provided with a closed-loop radiallyguiding groove having an approximate 0- form with respect to the tenssprocket of the next higher located amount-control device and extendingin circular arcforming manner within range of the counterwheels of saidcarriage means.

4. A tens-control apparatus according to claim 3, in which saidtens-control-ring body is pivotally swingable into tenscontrol positionagainst force of said spring means through said tens-control cam meanseffective upon a tens-control lever, a stop nose on said ring body, anda releasable opposing part against which said stop nose latches neartermination of each calculating shaft rotation.

5. A tens-control apparatus according to claim 3, in which saidtens-control-ring body is made of readily workable material, especiallya tough elastic, molded thermoplastic synthetic material.

